The present disclosure relates to an apparatus for driving an interior permanent magnet synchronous motor (IPMSM) and a method of controlling the apparatus.
An IPMSM that is driven using an inverter is mainly applied as a traction electric motor of electric vehicles or hybrid vehicles. In this kind of application field, an IPMSM is driven in a torque control mode, and a vector control in which a magnetic flux current and a torque current are independently controlled is performed.
Also, a range of a driving speed of a rotor of the IPMSM used in electric vehicles or hybrid vehicles is very broad, and thus the range frequently includes up to a flux-weakening control 2 range among driving ranges. The flux-weakening control 2 range exists only when center of a voltage limit ellipse of an IPMSM is within a current limit circle.
In general, in the flux-weakening control 2 range, only a voltage limit condition functions as a driving limit condition of the IPMSM, and an amount of a DC-link voltage of an inverter is limited, and thus, it is advantageous to use the voltage limit condition as much as possible in terms of output torque.